6.2 Trigonometric Functions: Unit Circle Approach/98

$f(\theta )=\sin(\theta )$
$g(\theta )=\cos {(\theta )}$
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle \theta = 60^{\circ}}

$g\left({\frac {\theta }{2}}\right)=g\left({\frac {60}{2}}\right)=g(30)$